This invention relates to mechanisms useful in the strangulation of tubular members. Specifically, it is directed toward devices including hemostatic clips useful in the strangulation of blood vessels and other fluid ducts in the human body.
The particular application of this invention to the strangulation of blood vessels will serve as an illustration of the inventive concepts enclosed herein. It will be appreciated, however, that the mechanisms embodying the concepts of this invention can be adapted for the closing of other tubular structures at intermediate points as well as near their open ends.
In the course of a surgical operation, a surgeon must often sever one or more blood vessels. It is desirable to provide means for closing the ends of the severed vessels, at least until the end of the operation, to stop bleeding that could interfere with the performance of the operation as well as present unnecessary risks to the patient.
Conventional means for closure consist of ligatures or the like tied about the individual vessels at the desired point of strangulation. The customary technique provides for the separate clamping of each vessel after the incision has been made. After clamping the vessels, a ligature is secured about each vessel providing closure and permitting the removal of the clamps. In some instances a great number of vessels must be severed after requiring one or more hours for proper closure at which point the operation may proceed. It will be apparent that an improved technique for closure will not only obviate the excessive expenditures of time by the surgeon and his assistants under conventional practice but also the dangers to the patient inherent in any delay.
It is an object of this invention to provide mechanisms for use in the strangulation of blood vessels and the like whereby the time required for closure is materially reduced and whereby bleeding can be terminated without the use of the excessive combination of clamping and tying operations.
It is a more particular object of this invention to provide improved mechanisms for the strangulation of blood vessels and the like whereby the blood vessels may be sealed off in a highly efficient manner to prevent bleeding during an operation and whereby the operation can proceed with a minimum loss of time as well as blood thereby to maintain conditions most favorable to the patient.
Hemostatic clip systems are known in the prior art. In particular, the closest prior art of which applicants are aware include the following U.S. patents, all of which were developed by one or both of the named inventors of the present application: U.S. Pat. Nos. 3,326,216, 3,363,628, 3,270,745, 3,439,522, and 3,439,523. In each of these referenced patents there is disclosed a hemostatic clip, a clip applicator and a cartridge in which the clip is stored until withdrawn by the applicator for use. With respect to the cartridge and clip a problem with the prior devices has been the tendency of the clip to bind against the central support of the cartridge during removal of the clip therefrom. Since the cartridge is usually made of plastic while the clip is usually formed of stainless steel or the like, if the clip is too securely tensioned on the central support it will stick or bind and is difficult to remove from the cartridge.
Removal of the clip is even more troublesome if the clip is provided with raised friction surfaces on the inside thereof, which surfaces are especially beneficial for insuring that the clip remains securely attached to a blood vessel. Often where such a raised occlusive surface is provided plastic will be torn away from the central binding post during removal of the clip from the cartridge. This is highly undesirable. As a result of these problems, it has not heretofore been practical to provide the desirable raised occlusive surfaces on the inside of the clip. Instead, as illustrated in the referenced patents, various recessed clip designs have been utilized.
According to one aspect of the present invention an improved cartridge is provided in which the clip is not secured in the cartridge by intimate engagement with the central post. Instead, it is maintained within its compartment by a strip of tape or other fabric placed across the top of the compartment and then severed. The flap end of the severed tape acts as a "swinging door" to retain the clip until needed and then to permit easy removal from the compartment.
Having solved the problems inherent in the prior art cartridges it then becomes possible to provide improved hemostatic clips which can have the desired raised occlusive surfaces on their internal surfaces.
Another feature of the present invention is the provision of an improved clip applicator. A serious problem with the clip applicator is the normal tendency of the surgeon to anticipate application of the clip to a blood vessel by slightly and unconsciously opening the scissor-like device as it is being used to guide the clip in place over the blood vessel. When this occurs, in the absence of any restraining devices, the clip is prematurely released from the jaws of the applicator. To prevent this from occurring it has been known in the prior art (see U.S. Pat. No. 3,326,216) to try and limit the outward movement of the jaws. In the patent just referenced this was accomplished by use of a leaf spring connected to one leg of the instrument and engaging a limiting hook provided on the opposite leg. While somewhat successful a more secure way of limiting the jaw travel is desired.
It is accordingly an object of the present invention to provide an improved system for applying hemostatic clips.
A further object of the invention is to provide an improved cartridge for hemostatic clips in which the cartridge is not secured to the central binding post.
Another object of the invention is to provide an improved hemostatic clip having a plurality of raised projections on the internal surfaces thereof.
A further object of the invention is to provide an improved clip applicator which securely limits the travel of the applicator jaws during use to prevent loss of the clip.
Other objects and advantages of the invention will be apparent from the remaining portion of the specification.